fix(model): 支持不设置推理强度

internal/backend/server/config/types.go

@@ -141,8 +141,8 @@ func NormalizeModelAdapterConfigs(input []ModelAdapterConfig) ([]ModelAdapterCon
 			return nil, errors.New("模型适配器 tooltipData 不能为空")
 		case next.ModelID == "":
 			return nil, errors.New("模型适配器 modelID 不能为空")
-		case next.Type == "openai" && next.ReasoningEffort == "":
-			return nil, errors.New("模型适配器 reasoningEffort 仅支持 low、medium、high、xhigh、max")
+		case next.Type == "openai" && !isSupportedReasoningEffort(next.ReasoningEffort):
+			return nil, errors.New("模型适配器 reasoningEffort 仅支持空值、low、medium、high、xhigh、max")
 		case next.Type == "openai" && next.OpenAIEndpoint == "":
 			return nil, errors.New("模型适配器 openAIEndpoint 仅支持 /v1/responses、/v1/chat/completions 或 /custom（自定义路径）")
 		case next.Type == "openai" && next.OpenAIExtraParamsEnabled:
@@ -224,13 +224,15 @@ func validateHeadersJSON(value string) error {
 }
 
 func normalizeReasoningEffort(value string) string {
-	switch strings.ToLower(strings.TrimSpace(value)) {
-	case "", "medium":
-		return "medium"
-	case "low", "high", "xhigh", "max":
-		return strings.ToLower(strings.TrimSpace(value))
+	return strings.ToLower(strings.TrimSpace(value))
+}
+
+func isSupportedReasoningEffort(value string) bool {
+	switch value {
+	case "", "low", "medium", "high", "xhigh", "max":
+		return true
 	default:
-		return ""
+		return false
 	}
 }
 

internal/backend/server/config/types_test.go

@@ -58,3 +58,25 @@ func TestNormalizeModelAdapterConfigsUsesStableExplicitSort(t *testing.T) {
 		}
 	}
 }
+
+func TestNormalizeModelAdapterConfigsAllowsBlankReasoningEffort(t *testing.T) {
+	adapter := testModelAdapter("non-reasoning-model", 1)
+	adapter.ReasoningEffort = ""
+
+	adapters, err := NormalizeModelAdapterConfigs([]ModelAdapterConfig{adapter})
+	if err != nil {
+		t.Fatalf("NormalizeModelAdapterConfigs returned error: %v", err)
+	}
+	if got := adapters[0].ReasoningEffort; got != "" {
+		t.Fatalf("ReasoningEffort = %q, want blank", got)
+	}
+}
+
+func TestNormalizeModelAdapterConfigsRejectsUnknownReasoningEffort(t *testing.T) {
+	adapter := testModelAdapter("invalid-reasoning-effort", 1)
+	adapter.ReasoningEffort = "unsupported"
+
+	if _, err := NormalizeModelAdapterConfigs([]ModelAdapterConfig{adapter}); err == nil {
+		t.Fatal("NormalizeModelAdapterConfigs should reject an unknown reasoning effort")
+	}
+}

internal/backend/server/upstream/mocks.go

@@ -835,7 +835,7 @@ func defaultThinkingEffortForAdapter(adapter legacyruntime.ModelAdapterConfig) s
 	if strings.EqualFold(strings.TrimSpace(adapter.Type), "anthropic") {
 		return normalizeAvailableModelThinkingEffort(adapter.AnthropicThinkingEffort, true, "xhigh")
 	}
-	return normalizeAvailableModelThinkingEffort(adapter.ReasoningEffort, true, "medium")
+	return normalizeAvailableModelThinkingEffort(adapter.ReasoningEffort, true, "disabled")
 }
 
 func normalizeAvailableModelThinkingEffort(raw string, allowMax bool, fallback string) string {

internal/backend/server/upstream/mocks_test.go

@@ -28,6 +28,40 @@ func TestBuildCLIModelDetailsPreservesChannelMetadata(t *testing.T) {
 	}
 }
 
+func TestDefaultThinkingEffortForOpenAIAdapterUsesDisabledWhenUnset(t *testing.T) {
+	adapter := legacyruntime.ModelAdapterConfig{Type: "openai", ReasoningEffort: ""}
+
+	if got := defaultThinkingEffortForAdapter(adapter); got != "disabled" {
+		t.Fatalf("default thinking effort = %q, want disabled", got)
+	}
+}
+
+func TestBuildAvailableModelEntriesUsesDisabledVariantWhenReasoningEffortUnset(t *testing.T) {
+	entries := buildAvailableModelEntries([]legacyruntime.ModelAdapterConfig{{
+		ID:          "channel-a",
+		DisplayName: "Model A",
+		ModelID:     "model-a",
+		Type:        "openai",
+	}})
+	if len(entries) != 1 {
+		t.Fatalf("entry count = %d, want 1", len(entries))
+	}
+
+	variants, ok := entries[0]["variants"].([]map[string]any)
+	if !ok {
+		t.Fatalf("variants type = %T, want []map[string]any", entries[0]["variants"])
+	}
+	if len(variants) == 0 {
+		t.Fatal("variants should not be empty")
+	}
+	if got := variants[0]["variantStringRepresentation"]; got != "channel-a:disabled" {
+		t.Fatalf("first variant representation = %#v, want channel-a:disabled", got)
+	}
+	if got := variants[0]["isDefaultNonMaxConfig"]; got != true {
+		t.Fatalf("disabled variant default flag = %#v, want true", got)
+	}
+}
+
 func TestEncodeCLIModelsUsesAgentModelDetailsWireFormat(t *testing.T) {
 	payload := map[string]any{"models": buildCLIModelDetails([]legacyruntime.ModelAdapterConfig{{ID: "channel-a", DisplayName: "Model A", APIKey: "provider-secret", BaseURL: "https://provider.example/v1"}})}
 	encoded, err := encodeMockProto("aiserver.v1.GetUsableModelsResponse", payload)